#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef double db;

#define in read()
#define pii pair<int,int>
#define fi first
#define se second
#define FILE(x) freopen(x".in","r",stdin);\
	freopen(x".out","w",stdout);
#define pb push_back

int read(){
	int x = 0,sgn = 1;char ch = getchar();
	for(;!isdigit(ch);ch = getchar()) if(ch == '-') sgn = -1;
	for(;isdigit(ch);ch = getchar()) x = (x<<1)+(x<<3)+(ch^48);
	return x*sgn;
}

const int N = 11000;
const int inf = 0x3f3f3f3f;

int h[N],S,T,nodenum,now[N],d[N],cnt = 1,n,m,a[N],id[110][110],D[110][110],ans,maxflow;
struct edge{int v,w,nxt;}e[N<<2];
void link(int x,int y,int w){e[++cnt] = (edge){y,w,h[x]};h[x] = cnt;e[++cnt] = (edge){x,0,h[y]};h[y] = cnt;}

bool bfs(){
	queue<int> q;q.push(S); memset(d,0,sizeof(d)); d[S] = 1; now[S] = h[S];
	while(q.size()){
		int x = q.front();q.pop();
		for(int i = h[x],y;i;i = e[i].nxt){
			if(!d[y = e[i].v] && e[i].w){
				d[y] = d[x] + 1; now[y] = h[y];
				q.push(y); if(y == T) return 1;
			}
		}
	}return 0;
}

int dfs(int x,int flow){
	if(x == T) return flow; int res = flow;
	for(int i = now[x],y;i&&res;i = e[i].nxt){
		now[x] = i;
		if(d[y = e[i].v] == d[x] + 1 && e[i].w){
			int k = dfs(y,min(res,e[i].w));
			if(!k) d[y] = 0; res -= k; e[i].w -= k; e[i^1].w += k;
		}
	}return flow - res;
}

int main (){
#ifndef ONLINE_JUDGE
	freopen("1.in","r",stdin);
#endif
	n = in,m = in;int mx = 0;for(int i = 1;i <= n;i++) a[i] = in,mx = max(a[i],mx);
	S = 0,T = ++nodenum;
	for(int i = 1;i <= n;i++) for(int j = i;j <= n;j++) D[i][j] = in,id[i][j] = ++nodenum;
	for(int i = 1;i <= n;i++)
		for(int j = i;j <= n;j++){
			int c = D[i][j];
			if(i == j){
				link(id[i][j],nodenum + a[i],inf); c -= a[i];
			}else link(id[i][j],id[i+1][j],inf),link(id[i][j],id[i][j-1],inf);
			if(c > 0) link(S,id[i][j],c),ans+=c;else link(id[i][j],T,-c);
		}
	for(int i = 1;i <= mx;i++) link(++nodenum,T,m*i*i);
	int flow = 0;while(bfs()) while(flow = dfs(S,inf)) maxflow += flow;
	printf("%d\n",ans-maxflow);
	return 0;
}
